Coiling machine for fine wire



Patented Mar. 20, 1945 Fred B. Iden, Cleveland Heights, Ohio, assignorto General Electric Company, a corporation of New York Application May5, 1941, Serial No. 391,882 1s claims. (o1. 14o-71.5).l

My invention relates to methods and apparatus for making laments andother types of resistance elements, such as electrodes, for incandescentand discharge lampsv as well as other similar devices. Moreparticularly, my invention relates to a method and apparatus for coilingand otherwise shaping such filaments or resistance elements.

It is desired that such filaments have certain definite shapes in orderto reduce the complexity and increase the performance and life of theelectrical devices in which they are used. It has not heretofore beenpossible to manufacture certain preferred forms 'of filaments so cheaplyand readily as to make them available for the less expensive electriclamps and similar devices. Anobject of my present invention is toprovide a method and automaticapparatus for producing such elementscheaply on a commercial scale. Another object of my invention is toprovide automatic apparatus for making resistancev elements,particularly filaments, having a coiled mid-portion and specificallyshaped end or leg portions.

Another object of my invention is to provide apparatus for reshaping theend or leg portions of a filament. Other objects and advantages of myinvention will appear from the following detailed description and fromthe drawing.

In the drawing, Fig. 1 is a side elevation of apparatus comprising myinvention with a transfer mechanism in the process of carrying afilament from the coiling apparatus to the leg shapping mechanism; Fig.`2 is a horizontal section through the coiling apparatus; Fig. 3 is aside elevation of the leg shaping mechanism at 90 degrees to that ofFig. 1 and with onev portion broken therefrom along the line 3-3 of Fig.1;

A (Fig. 1) and a second shaping operation at B.

The coiling operation, in-particular, is preferably performed byapparatus of the general type ydisclosed in the Illingworth Patent1,771,927, although itis preferred that the specic apparatus correspondto that disclosed in Iden Patent 2,179,296 in that such apparatusperforms the ticularly well adapted to operate withfthe presentapparatus comprising my invention. The essential parts of said coilingapparatus, which are shown midway through their cycle of operation inFig.2, start each cycle of operation with a movement of the coiling headI0 toward the mandrel I I and spindle I2. At this time, the mandrelIlextends from the spindle I2 as shown and a short end of the filamentwire I3 extends from the coiling head I0.' The shoe I4 on the end of thejaw I5 is also separated fromthe spindle I2 at this time so thatthe-forward movement of the coiling head I0 can continue until the endof'said filament wire I3 is located over the shoulder I6 of the spindleI2. During the movement, the mandrel II passes into the opening Il ofthe coiling head I0, which is parallel to that containing j from thespindle I2 at a very definite rate to cause the filament wire I3 to bewound around said mandrel II at a desired pitch. The coiling operationis complete when the correct number of turns have been made to form thecoils of the center section I8 of a filament although the axial movementof the coiling head I0 continues until it takes the position shown inFig. 2 before it stops.

At this time, the center coiled portion I8 of a filament is wound aroundthe mandrel II and the opposite end or leg portionsv I9 and 2U extend inopposite directions therefrom. The end or leg portion 20 of the filamentwire I3 between the coils I8 and the coiling head I0 differs from thatat the opposite end of the coils I8 in that it is double. said leg orend portion 20 and in the next operation is cut in two by movement ofthe knives 2| and 22. This operation establishes the length o1' thefilament 23 which is comprised of a coiled portion I8 and the end or legportions I9 and 20' ofl equal length and allows an end section .20" oftheflamcnt wire I 3 to extend beyond the coiling head I0 having alengthcorrelaps the last step in that the stationary and movable jaws 24 and25 of the transfer mechanism engage and prepare to grip the coiledportion I8 of the filament 23 before it is stripped from the mandrel Thetransfer mechanism corresponds closely to the mechanism disclosed inIllingworth Patent 1,733,882 assigned to the present assignee, andcomprises a stationary jaw 24 attached to the arm 26 and a movable jaw25 slidable in ways in the stationary jaw 24. rAt the moment the jaws 24and 25 are carried to A, the roller 21 on the end of the lever 28 is inengagement with a high part of cam 29, and said lever 28, which isconnected to :jaw 25 through link 38, holds said jaw 25 in the openposition. The lever 28 is pivoted on the screw 3| held by arm 26 and,being under the influence of the spring 32, is turned about 'said screw3| in accordance with the changes in shape of the cam 29. When thetransfer mechanism is at its limit of movement, the arm 26 engages thestationary stop screw 33 in the adjacent portion 34 of the apparatus andthe coiled portion I8 of the filament 23 is within a V notch in thestationary jaw 24. During this latter interval the jaw I on the spindleI2 is moved sideward so that the end or leg portion |9 of the filament23 is released and the mandrel II is drawn into the spindle I2 so thatthe filament 23 is stripped therefrom. The stripping operation ispossible only because the coils I8 have unwound a fraction of a turn dueto the release of the end or leg portion 28' in the last period ofoperation. The

next operation follows immediately and consists in a movement of the`jaw 25 which causes it to engage and grip the filament 23. The jaw 25is actuated by the rotative movement of the cam 29 which carries a lowportion thereof below the roller 21 and occurs so rapidly after themandrel |I is withdrawn that the filament 23 does not turn or twist fromits known position. The following transferring operation is the resultof a swinging movement of the arm 26 which carries it against the stopscrew 35 and carries the filament 23'into the shaping mechanism at ment23 is still tightly gripped by the transfer mechanism. The transfermechanism now functions as a holder for the filament while the shapingoperation is being carried on since the jaws 24 and 25 form the coiledportion I8 thereof into a rigid mass which does not allow the end or legportions I9 and 2l' to move out of position during said operation.. Thismethod of operation is preferred because the filament 23 tends to turnout of position since it has, prior to the time it was gripped by thetransfer mechanism, uncoiled a portion of a turn and the end or legprtions I9 and 2l' are no longer in the same plane.

When the transferring operation has beencompleted, the fingers 31 and 33are moved down so as to clamp a short section of the les portions I9 and2l' next to thecoiled portion I8 to the arms 3l'38 of the die block 36.The upper ends of said arms 3l'33' constitute separated supports for thefilament ends. The fingers 31 and 38 are in reality separate slideswithin ways formed by the standard 39, the cover plate 48 and the slideblocks 4| and 42 (Fig.- 3) and are moved by the expansion of springs 43(partly enclosed in a well, in each finger) when the pin 44 movesdownward. The springs 43 butt against the cap plate 45 attached tostandard 39, whereas the pin 44 is carried by a slide 46 in ways in theback of the standard 39 and extends through a slot in said standard 39to adjacent slots in the back of the fingers 31 and 38. A U-shapedspring 41 in corresponding slots in the front face of the fingers 31 and38 absorbs all lateral freedom of movement thereof so that they retainvery definite positions at all times.

-The downward movement of the fingers 31 and 38 is matched by acorresponding movement of the movable dies 41 Aand 48 located adjacentthereto which movement ls continued until the dies have wiped the legsof said filament 23 down about the shaped sides cf the die block 36 asshown in Figs. 3 and 5.

The movable dies 41 and 48 are partially located within slots in theslide blocks 4| and 42 respectively and are carried downward by thecorresponding movement of said slide blocks 4I and 42 and slide 46 whichare interconnected by the pins 49; Slots 59 in the standard 39 give thepins 49 freedom vof movement whereas pins 5| attached to slide blocks 4|and 42 provide a positive-means of attaching the movable dies 41 and 48and the slide blocks 4| and 42 together. Springs 52, which are locatedbetween the slide blocks 4| and 42 and an extending arm of the movabledies 41 and 48, keep said dies 41 and 48 against the fingers 31 and 38and the legs I9 and 28'- of the filament 23 during most of the period oftravel thereof but at the end of said travel the oblique end surfaces 53of said dies 41 and 48 engage the ends of screws 54 and 55 and areforced` inward. This latter movement of the dies 41 and 48 forces thelegs |9 and 20' of the filament 23 tightly against the die block 36 andcompletes the shaping operation.

The movable dies 41 and 48 and thengers 3 1 and 38 are now returned totheir former position in order that the filament 2.3 can be removed fromthe .shaping mechanism. The return movements of the apparatus are inreverse order to the other movements thereof and are caused by an upwardmovement of the slide 46. The slide 48 is located in ways in the back ofthe standard 39 in which it'is held by the rplate 56 and is connectedthrough yoke 51 and rod 58 to cam actuated means (not shown) connectedto the coiling apparatus and transfer mechanism in order that it and theshaping mechanism will be operated at proper intervals.

The filament 23 is released from the transfer mechanism prior'to beingtaken from the shaping mechanism by a rotative movement of the.

paratus and of pushing the filament 23 from the shaping mechanism sothat it falls into the chute 59 and is carried away from the apparatus.

At this time, the lament 23 (shown in Figs. 6 and '1) is comprised ofacoiled mid-portion II, relatively short leg portions 66 lying verygenerally in a. plane parallel to the axis of the coiled portion I8, andlonger leg portions II odset from opposite sidesof the 'coiledmid-portion Il and tions to ,spring back to the above position al-Vthough they were bent to the more oblique faces of the die block 36. Thevery ends 62 of the :til-

ament'legs I9 and 20' retain the greater portion of the bend which theyhave received, however, and are located at still another position.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is: v

1. Apparatus for forming fllamentary resistance elements for electricaldevices from a wire comprising a mandrel, means for coiling a portion of.the v.wire about the mandrel with a free end portion extending outwardsubstantially parallel to the axis of the coil, means for stripping thecoiled portion of the wire from said mandrel, means for gripping thewire at its coiled portion and transferring it to another location andend portion of said wire so that it extends laterally of the axis ofthecoil in a definite predey ring means being constructed and arranged tohold the filament in delinite predetermined relation to said means forbending the wire.

2. Apparatus for forming fllamentary resistance elements for electricaldevices from a wire comprising a mandrel, means for coiling a portion ofthe wire about the mandrel with free end portions extending outwardsubstantially parallel to the axis of the coil, means for stripping thecoiled portion of the wire from said mandrel, means located adjacent thecoiling apparatus for bending theend portions of the wire so that theyextend laterally of the axis of the coil in a deiiportion of the wire,adie adapted'to engage sections of both uncoiled portions of said wireextending beyond the' coiled portion, fingers adapted to clamp saidsections of the wire against the die, movable dies adapted to bend thefree portions of said uncoiled end portions of. the wire termineddirection, said gripping and transferportion of the wire, means locatedadjacent the coiling means for shaping the wire comprising a die adaptedto engage sections of both uncoiled portions of said wire extendingbeyond the coiled portion, ngers adapted to clamp said sections of thewire against the die, movable dies adapted to bend the free portions ofsaid uncoiled end portions of the wire intjo engagement withtherstmentioned die to shape them and means for actuating the ngers andmovable dies at proper intervals, and means gripping the coiledportionof the wire for transferring it to the last-mentioned means andholdingit in position during the axis of the coil, a die member having sidessloping obliquely inward and downward from its .upper edges, means forholding the filament on said die with its said end. portions extendingacross the said edges of the die and laterally outi' tioned die memberarranged to bend said iilament end portions down around the said edgesof said first-mentioned die member and then against its said -slopingsides.

7. In a device of the 'character described for reshaping the ends of alament coil having straight end portions extending'outward from oppositeends of the coil substantially parallel t0 the axis of the coil, a diemember having sides sloping obliquely inward and downward from its upperedges, means for holding the filament on said die with its said endportions extending l across the said edges of the die and laterally intoengagement with the first-mentioned die to shape them and means foractuating the nger v and movable dies at proper intervals. f

4. Apparatus for forming filamentary resistance elements for electricaldevices from a wire comprising Imeans for coiling an intermediateportion of the wire, a die adapted to engage sections of both uncoiledportions of said wire ex tending beyond the coiled portion, fingersadapted to clamp said sections of the wire against the die, movable diesadapted to bend the free portions of said uncoiled end portions of thewire into engagement with the first-mentioned die to shape them, springsurging the iingers toward .the said first-mentioned die and the wire,means controllingthe movement of said lingers for carrying the movabledies against said wire to bend the end portions over the saidrst-mentioned die, and separate means for forcing the movable diestoward said first-mentioned die to bend said outward beyond its saidsides, means for clamping the filament end portions against said diemember adjacent its said upper edges, and movable die members onopposite sides of said firstmentioned die member Iarranged to bend saidfilament end portions down around the said edges of said first-mentioneddie member and then against its said sloping sides.

8..In a device of the character described for reshaping the ends of afilament coil having straight end portions extending outward fromopposite ends of the coil substantially parallel to the axis of thecoil, a die member having sides sloping obliquely inward and downwardfrom its upper edges, means for holding the filament on said diewith itssaid end portions extending acrossthe said edges of the die andlaterally outward beyond its saidsides, a pair of clampfilament downaround thesaid edges of said rstmentioned die member',v and means forthen causing said movable die members to move inwardly to press the saidfilament end portions against the sloping sides of said first-mentioneddie member.

9. In a device of the character. described for reshaping the` ends of afilament coil having straight Yend portions extending outward fromopposite ends of the coil substantially parallel to the axis of thecoil, a 'die member having sides sloping obliquely inward and downwardfrom its upper edges, means for holding the filament on said die withits said end portions extending across the said edges of the die andlaterally outward beyond its said sides, a pair of independently movableclamping iingers mounted above said die member, movable die membersmounted above said first-mentioned die member on opposite sides of saidclamping fingers, and means forv moving said clamping fingers andmovable diev members downward to iirst cause each of said lingers toclamp 'a part of an end portion of the lament with a definite pressureagainst said first-mentioned die adjacent one of its said upper edgesand to then cause said movable dier members to bend the free endportions of said iilament down around the said edges of saidfirst-mentioned die member, and means for then causing said movable diemembers to move inwardly to press the said filament end portions againstthe sloping sides of said first-mentioned die member.

10. In a device *of the character described for reshaping the ends of aiilament coil having straight end portions extending outward from lopposite ends of the coil substantially parallel to the axis of thecoil, a die member having sides sloping obliquely inward and downwardfrom its upper edges, means for holding the lament on said die with itssaid end portions extending across the said edges of the die andlaterally outward beyond its said sides, a pair of slide members mountedabove said die member and each carrying a downwardly extending clampingiinger movably mounted in said slide in alignment with one of the saidedges of said die member, an angular movable die member pivotallymounted on each of said slide members at one side of the adjacentringer, each of said movable die members extending downward from itspivot and then laterally toward the adjacent finger, means resilientlyurging each of said die members about its pivot to hold its end againstthe adjacent nger, means for moving said slide members downward tofirstl cause said fingers to clamp parts of the end portions of thelament against said iirst-men-tioned die member and, upon furthermovement, to cause said ends of the movable die members to bend the freeend portions of the filament down 'around the said edges of saidinst-mentioned die member, and means for then causing said movable diemembers to be pivoted under added pressure to press the said iilament lyond the supports, clamping said end portionsv against said supports,and then bending the said end portions around said supports so that theyextend laterally of the coil axis.

12. Apparatus for forming filaments for electric lamps and similardevices comprising means for coiling an intermediate portion of acontinuous length of wire into a compact helix with the straight endportions extending outward parallel to the axis of the coil, a diecomprising separated support arms, means for gripping the coiled portionof the filament and transferring it from the coiling means to the die, aportion of the said gripping and transferring means being shaped to fitin the space between the die arms to hold the filament with its endportions extending across and beyond the sides of said die arms, ngermeans adjacent said die arms adapted to clamp said iilament end portionsagainst said die arms, movable die means adapted to bend the freeextremities of said filament end portions into engagement with the sidesof said die arms to shape them, and means for actuating the finger meansand movable die means at proper intervals.

13. In apparatus of the class described for reshaping the ends of alament coil having straight end lportions extending outward fromopposite ends of the `coil substantially parallel to the axis of thecoil, a die member comprising separated support arms, means for holdinga filament on said die member with its said end portions extendingacross said die arms and beyound 'the sides thereof, linger meansIadjacent said die arms adapted to clamp said filament end portionsagainst said die arms, movable die means adapted to bend the freeextremities of said lament end portions into engagement with thek sidesof said die arms to shape them, and means for actuating the iingen'meansand movable die means at proper intervals.

FRED B. IDEN.

